All meetings take place on Thursdays, 3.30-5.30 pm in Bioscience Research
Building 1103, unless otherwise indicated.

September 9
Bradley Postle (Psychology,
University of Wisconsin-Madison)

Title: Exploring working memory: The
functions and physiology of delay-period activityAbstract:
At least since the time of Hebb (1949), a
governing assumption in psychology and neurophysiology has been that the
short-term retention of information is accomplished via activity that spans
the delay separating the prehension of information and the subsequent use of
that information to guide behavior. The advent of "information-based"
analysis techniques provides the opportunity to refine this assumption by
assessing the nature of the information being represented across the delay
period rather than simply the level of activity in different brain areas.
Indeed, the results from recent studies in our laboratory challenge the very
assumption that delay-period activity, as measured with functional magnetic
resonance imaging (fMRI), is primarily mnemonic in nature, and instead
suggest an intriguing alternative. In parallel, to better understand the
physiological properties of delay-period activity, we are pairing
electroencephalogram (EEG) recording with simultaneous delivery of
high-frequency repetitive transcranial magnetic stimulation (rTMS). These
studies are revealing important roles for neuronal oscillations in several
discrete frequency bands, and in several discrete brain systems, in
determining individual differences in performance on tests of short-term
memory. Together, these studies illustrate how, with the application of
cognitive neuroscience techniques, categorical thinking about cognitive
constructs such as "working memory" is giving way to a more empirically
grounded understanding of how the brain supports complex behaviors.

Title: The Computational Nature and Neural Organization of
Sensory-Motor Integration in Speech ProcessingAbstract: Sensory-motor integration in the domain of speech
processing is an exceptionally active area of research and can be summarized
by two main ideas: (1) the auditory system is critically involved in the
production of speech and (2) the motor system is critically involved in the
perception of speech. Both ideas address the need for parity, as Liberman
put it, between and the auditory and motor speech systems, but emphasize
opposite directions of influence. Somewhat paradoxically, it is the
researchers studying speech production who promote an audio-centric view and
the researchers studying speech perception who promote a motor-centric view.
Even more paradoxically, despite the obvious complementarity between these
lines of investigation, there is virtually no theoretical interaction
between them. I will consider the relation between these two ideas regarding
sensory-motor interaction in speech and whether they might be integrated
into a single functional anatomic framework. To this end, I will
review evidence for the role of the auditory system in speech production,
evidence for the role of the motor system in speech perception, and recent
progress in mapping an auditory-motor integration circuit for speech and
related functions (vocal music). We will then consider a unified framework
in which sensory-motor integration functions primarily in support speech
production in an audio-centric fashion, but can also subserve top-down motor
modulation of the auditory system during speech perception. The role of the
purported "mirror system" in these circuits will also be addressed. Finally,
I discuss a range of possible clinical correlates of dysfunction of this
sensory-motor integration circuit.

Title: Understanding Communication in
InfancyAbstract: Humans
routinely engage in complex communicative interactions. As adults, we
recognize that speech and gestures can communicate even if we cannot
understand the specific content, for instance when listening to speakers
converse in a foreign language or use unfamiliar gestures. A fundamental
question in development is how infants come to realize that speech and
gestures are means for communication, allowing one person to transfer
information to another. I'll present a series of studies in which we examine
how infants evaluate the success of communicative interactions between a
sender and receiver from a third-party perspective. Before they produce or
comprehend many words or gestures, preverbal infants have some understanding
of how they are used by others. This early communicative competence may
provide infants with a channel for learning from others and lay a foundation
for our social and cultural life as humans.

Title: Putting Thought Into
ActionAbstract: For your thoughts to be
useful, they must be enacted. This is true even for mundane thoughts like
those for getting up out of your desk chair, leaving your office, going to
the room where this talk will be given, making your way to your seat, and
settling in to hear about research on the planning and control of everyday
actions. The research to be described will draw on evidence from
neurophysiology, behavioral science (human and non-human), and computational
modeling. A view that all these lines of evidence support is that goal
postures are specified before movements are planned and performed. Motor
control, you will hear, is more cognitively rich than some have realized.

Title: Thinking in a Foreign LanguageAbstract:
We explore how the use of a foreign tongue affects the nature of judgment,
decision and choice. In general, there is evidence that a foreign tongue is
less emotionally anchored than a native tongue. We therefore hypothesize
that decisions made in a foreign language are more muted emotionally. We
show that as a result, the use of a foreign tongue reduces or eliminates
certain judgmental biases. We also show that when choice could benefit from
an emotional reaction, a foreign tongue reduces such benefit. These results
add new theoretical perspective to considerations of language and thought,
and they have important implications for millions of people who live and
work while using a language that is not their native tongue.

Title: What do human infants expect when adults communicate to
them?Abstract: While social learning and communication are both widespread
in non-human animals, social learning by communication is probably human
specific. Humans can and do transmit generic knowledge to each other about
animal and artifact kinds, conventional behaviors to be used in specific
situations, arbitrary referential symbols, cognitively opaque skills, and
know-how embedded in means-end actions. These kinds of cultural contents can
be transmitted by either linguistic communication or nonverbal
demonstrations, and such types of knowledge transmission contribute to the
stability of cultural forms across generations.
In a series of studies, we have shown that human infants are
prepared to be at the receptive side of such communicative knowledge
transfer, which, together with adults' inclination to pass on their
knowledge to the next generation, constitute a system of 'natural pedagogy'
in humans. This talk will provide an overview of recent counterintuitive
findings that suggest that human infants process the same information
differently when it is presented to them by ostensive communication or
outside a communicative context. When toddlers observe an individual
expressing emotional attitudes towards objects, they attribute the
corresponding preferences to her, but not to others. However, when these
attitude expressions are performed for them, they generalize the
corresponding preferences to other people. Even younger infants tend to
encode kind-relevant properties, like shape and color, of objects at the
expense of ignoring their episodic properties, like their location and
numerosity, when the objects deictically referred by a communicator. We have
also found that infants represent artifacts in terms of their demonstrated
function, but only if this demonstration occurs in a communicative context.
Infants are also more likely to categorize objects on the basis of
communicated, as opposed to simply observed, information.
These results suggest that communicative contexts make
infants search for potentially generalizable semantic information, as if
they expected to learn something. These perceptual and cognitive biases
allow human infants to pay special attention to, and learn from, potential
teachers, and assist the acquisition of cultural knowledge in a uniquely
human way: by communication.

Title: Emotion, Embodiment, and AwarenessAbstract: Emotions influence cognition and behavior. But how?
I will argue that emotional influence often involves some form of
"embodiment" - an activation of somatosensory representation of emotion.
Specifically, I'll present studies showing that (i) perception and memory of
emotional expressions recruit facial feedback mechanisms, (ii) thinking
about abstract emotion concepts elicits somatosensory reactions, and (iii)
financial and consumption decisions are influenced by emotion stimuli to the
extent that these stimuli activate embodied responses. However, I will
also present evidence that some emotional tasks can be successfully
accomplished without any somatosensory recruitments, and discuss general
problems for a purely "embodied" view of emotional processing. Finally, I
will offer evidence for a tricky possibility that emotion, even when
represented in the embodiments and actions, can be unconscious, that is
remain hidden from the phenomenological experience ("feeling"). All
this enriches, but also challenges the "neo-Jamesian" views that tie
emotional processing and emotional experience to embodiment.